Writing instrument



FIG. 1 is a front elevational view of a writing instrument showing my new design, with a portion of the cap member broken away for convenience of illustration;

FIG. 2 is a top plan view;

FIG. 3 is a cross-sectional view taken along line 3--3 in FIG. 1; and

FIG. 4 is a bottom plan view thereof.

The rear of the writing instrument is a mirror image of the front. 

The ornamental design for a writing instrument, as shown and described. 